those boxes easily get dents and can even rupture with rough handling. now, if the purpose of the cardboard is just to keep things from falling on your circuit, and the circuit stays in your lab, then a 100% cardboard case may be okay

one more note: the procedure that is described on the page that you have mentioned is correct. But for the first experiments I suggest to use delay_step=0.5chip; Doppler_step=500Hz (bigger steps are possible but they result in additional losts in SNR and it's better to play with these values later). Record output from all 6 correlators (Ie, Qe, Ip, Qp, Il, Ql). After you record all values,...

I read on the page "ACCUM_INT period = (accum_divide + 1) / 16.384MHz For 0.5 ms accumulator interrupt accum_divide = 16.384x10^6 * 0.0005 - 1 accum_divide = 0x1FFF " - but if you use namuru clock 4 x 16.384 then you have to use this value it TIC_periode calculation

But without using printf-function the program worked incorrectly (it resarted acquisition very often). According to algorithm it should restart every 10 seconds but in fact it restarted 10 or more times faster. So it didn't work correctly but I couldn't check what was wrong because nor printf nor debug is working ;)